Power supply system for an electric vehicle and a cargo box

A cargo box for an electric vehicle, comprising:

• a cargo box battery pack;
• a number of cargo box electric arrangements, including a low voltage arrangement comprising:
• a cargo box system battery, for powering one or more cargo box electric systems;
• and
• a cargo box first converter, for converting power from the cargo box battery pack to the cargo box system battery;
• wherein the cargo box battery pack is configured to power the cargo box electric arrangements and a traction battery pack;
• a cargo box second converter, for converting power from a charging system to the cargo box battery pack;
• and
• a cargo box management unit, for acquiring one or more states of, and for controlling, parts of the electric vehicle assembly, and for communicating with a vehicle management unit;
• wherein a cargo box requested power (Pcs_to_cb) is the sum of a cargo box battery pack charging power (Pch_cb) and a cargo box electric arrangements power need (Parr_cb), and
• wherein the cargo box management unit continuously communicates the cargo box requested power (Pcs_to_cb), to the cargo box second converter.

A cargo box for an electric vehicle, comprising:

• a cargo box battery pack;
• a number of cargo box electric arrangements, including a low voltage arrangement comprising:
• a cargo box system battery, for powering one or more cargo box electric systems;
• and
• a cargo box first converter, for converting power from the cargo box battery pack to the cargo box system battery,
• wherein the cargo box battery pack is configured to power the cargo box electric arrangements and a traction battery pack;
• a cargo box second converter, for converting power from a charging system to the cargo box battery pack;
• and
• a cargo box management unit, for acquiring one or more states of, and for controlling, parts of the electric vehicle assembly, and for communicating with a vehicle management unit;
• wherein the cargo box electric arrangements are electric arrangements that require a higher voltage than the voltage supplied by the cargo box system battery, when fully charged.

A power supply system for an electric vehicle and a cargo box, comprising:

• an electric vehicle assembly, for being located on the electric vehicle, comprising:
• a drivetrain;
• a traction battery pack;
• a number of vehicle electric arrangements, including a low voltage arrangement comprising:
• a vehicle system battery, for powering one or more vehicle electric systems;
• and
• a vehicle first converter, for converting power from the traction battery pack to the vehicle system battery;
• wherein the traction battery pack is configured to power the electric arrangements and the drivetrain of the electric vehicle;
• and
• a cargo box assembly, for being located on the cargo box, comprising:
• a cargo box battery pack;
• a number of cargo box electric arrangements, including a low voltage arrangement comprising:
• a cargo box system battery, for powering one or more cargo box electric systems;
• and
• a cargo box first converter, for converting power from the cargo box battery pack to the cargo box system battery;
• and
• wherein the cargo box battery pack is configured to power the cargo box electric arrangements and the traction battery pack;
• and
• a cargo box second converter, comprising an AC/DC converter and a DC/DC converter, for converting power from a charging system to the cargo box battery pack, and from the cargo box battery pack to the traction battery pack;
• wherein the power supply system is configured for selectively switching between a number of modes, said modes comprising:
• a cargo box charging mode, wherein power is supplied from the charging system to the cargo box battery pack;
• an assembled drive mode, wherein power is supplied from the cargo box battery pack to the traction battery pack;
• and
• a separated drive mode, wherein the electric vehicle assembly and the cargo box assembly is not electrically connected and power is transmitted between the traction battery pack and the drivetrain;
• wherein, when the power supply system is in cargo box charging mode, the cargo box management unit calculates a cargo box requested power (Pcs_to_cb).